About the Glowatzki Laboratory

Mission Statement:

In the hearing organ in the inner ear, hair cells pick up the sound signal and send it to the brain via synapses between hair cells and auditory nerve fibers. Understanding how these synapses function is crucial for our understanding of how the sound signal gets processed and how hearing loss and other auditory pathologies like tinnitus in the inner ear occur. Additionally, the vestibular organ in the inner ear provides the brain with information about position and movement of our head in space. A loss of vestibular function can come with severe problems to lead our everyday lives. We therefore also study the mechanisms that underlie synaptic transmission between hair cells and vestibular nerve fibers in the vestibular periphery. The ultimate aim of our research is to develop strategies to prevent or cure hearing loss and vestibular dysfunction.

The approach of our lab focuses on studying the molecular mechanisms that shape synaptic activity. We use cutting edge technology to stimulate hair cells and nerve fibers with optogenetic methods, and we record hair cell and neuronal activity with electrophysiological methods like patch clamp or with calcium imaging. With confocal microscopy we analyze the localization of hearing related proteins in the inner ear. With collaborations within and outside Johns Hopkins we are able to integrate additional techniques into our projects, for a multifaceted approach.

Current research projects in the laboratory examine multiple aspects of inner ear synaptic transmission:

1) Mechanisms underlying release at the hair cell synapse; 2) Mechanisms underlying vestibular synapse function; 3) Different roles of type I and type II auditory nerve fibers; specifically type II nerve fibers may have a role in perceiving damaging sounds and pain in the inner ear; 4) Function of the lateral efferent system, a feedback system from the brain to the inner ear that modulates the processed sound signal on its way to the brain; 5) Repair of damaged synapses; 6) Regeneration of lost synapses.